The role of a meticulous oral hygiene program in reducing oral assessment scores, mucosal plaque scores, colonization of dental plaque and exposition to pathogen colonization that may lead to nosocomial respiratory infections in a selected ICU patient population. Critical care patients, especially intubated individuals, have the greatest risk of any hospitalized patient to acquire a nosocomial respiratory infection. The research reveals that the predominantly initial site of bacterial colonization is the oropharyngeal cavity. Oral colonization precedes pulmonary colonization, which ultimately leads to pneumonia. Nosocomial pneumonia causes the greatest mortality and morbidity in the Intensive Care Unit (ICU). Prevention of colonization at the oropharyngeal site could be an effective infection control measure. Dental plaque has been identified as a host for bacterial colonization in the mouth and has been significantly associated, (p< 0.001), with subsequent nosocomial infections. Dental plaque can act as a reservoir for pathogens in ICU patients. Aerobic pathogens are not normally associated with dental plaque. However, poor oral hygiene and lack of mechanical elimination of the plaque, begins a complex cascade of biological actions by which pathogen adhesion to mucosa and teeth substrates occurs. Additionally, neglected or insufficient mouth care is the foremost predisposing factor to oral conditions such as gingivitis, mucositis, and stomatitis, which supply additional ports of entry for pathogens. Meticulous oral hygiene is required to prevent colonization of dental plaque in ICU patients. There are only three known studies that show the type and frequency of oral hygiene required to prevent or decrease colonization and thereby reduces the incidence of nosocomial respiratory infection. This prospective randomize trial tested the effectiveness of a comprehensive and systematic oral care program to reduce the mucosal plaque scores, the oral assessment scores, and the incidence of respiratory infections in patients in two selected medical-surgical ICU ?s. Additionally consistency of oral hygiene was compared between the ICU whose nursing staff was followed "routine" care and the ICU whose nursing staff was given specific oral hygiene teaching by a dentist and a dental hygienist. The results of the study showed that oral care provision in the test ICU was significantly better during the critical care stay than the control ICU, p=0.001. Individualize oral care was determined from the results of oral assessment scores. The amount of microbiological inoculum was significantly lower in the test ICU, p=0.0094. Beck oral assessment scores improved in the test ICU, p= 0.0342 on day three of the ICU stay. Additional analysis continues. 23 Patients enrolled.